Federal land managers have adopted a new policy aimed at capping pipes and plastic tubes that unintentionally lead to the deaths of tens of thousands of cavity-dwelling birds and animals that think they've found a new home.

The effort includes the vent pipes on campground outhouses but the target is the millions of PVC pipes that were used for decades to stake mining claims under the General Mining Act of 1872.

Once inside, the cavity nesters, reptiles and small rodents often are unable to scratch their way back out because the plastic walls are too slick.

Bureau of Land Management Director Neil Kornze says the new policy requires agency personnel to identify and cap or screen survey markers, pipes, vents, signposts and fences.